The perimeter would be rational due to both the width and length being rational numbers. A rational number is a number that can be written as a fraction such as 8 it can be written as 8/1, but a irrational would be a decimal number which in this case there would be none because both length and width is rational number. For example, Lets say the width is 8 and the length is 10. once both are written into fraction form such as 8/1 and 10/1 we add them to get a perimeter of 18. Hope this helps! <span />